Speed measurement

Abstract

The invention relates to a speed measuring device. The aim of the invention is to allow a precise and flexible speed measurement. The aim is achieved, whereby emission components are transmitted through two different paths and detected. A modification to the phase shift between the emission components in both paths, in relation to a non-operating device, represents a rate for the actual speed of the device, for evaluation means. The influence of a rotary motion on a modification to the phase shift is thus prevented or compensated. The invention also relates to a system, provided with such a device, and to a corresponding method of speed measurement.

1 . A system, comprising: 
 at least one source designed for the generation of at least one emission,    at least six devices for the measurement of a speed, which are arranged in the system for the measurement of a speed and of a rotation of the system in different spatial directions, wherein each of the at least six devices ( 1 ;  2 ;  3 ;  4 ) exhibits at least two paths, on which, respectively, at least one part of the at least one emission generated by the at least one source propagates with a respective known wavelength and a respective known propagation speed, wherein the paths are formed in such a way that a translatory movement of the individual device causes a phase displacement between the emission parts propagated on the at least two paths of the device, and    evaluation means designed for the detection of emission parts which leave the respective at least two paths of the devices, and for the determination of the speed of each of the devices in at least one spatial direction, respectively, by the evaluation of a change in the phase displacement between the detected emission parts in comparison with a phase displacement with the device at rest,    wherein the system is designed in such a way that a change in the phase displacement of the emission parts detected by the evaluation means for respectively one of the devices due to a rotational movement of this device is prevented or compensated for.    
   
   
       2 . The system according to  claim 1 , wherein the at least two paths of a respective device exhibit different materials or different combinations of materials.  
   
   
       3 . The system according to  claim 2 , wherein the at least two paths ( 21 ,  22 ) of a respective device ( 2 ) exhibit different geometric lengths.  
   
   
       4 . The system according to  claim 3  wherein, in order to prevent a change in the phase displacement between the emission parts detected by the evaluation means due to a rotational movement of a respective device, each of the at least two paths of the device exhibits, outside an imaginary straight line, path parts of essentially equal size on opposite sides of this straight line.  
   
   
       5 . The system according to  claim 3 , further comprising detection means designed for the detection of a rotational movement of a respective device, wherein the evaluation means are designed for the compensation of a change incurred by a rotational movement on the at least two paths of the respective device in the phase displacement between detected emission parts on the basis of information from the detection means.  
   
   
       6 . The system according to  claim 5 , wherein the at least two paths of the respective device are designed in such a way that they exhibit at least one common path section, which is run through in opposite directions by the emission parts fed into the at least two paths.  
   
   
       7 . The system according to  claim 6 , wherein the common path section is designed in such a way that it exhibits a path part which is run through by one of the emission parts essentially in the direction of measurement of the respective device and a path part which is run through by this emission part essentially in the opposite direction, wherein the two path parts, with the device at rest, exhibit a different physical length.  
   
   
       8 . The system according to  claim 7 , further comprising an acceleration sensor designed for creating a reference to the local gravity normal.  
   
   
       9 . The system according to  claim 8 , wherein the at least six devices are arranged on the six faces of a cube, wherein the devices exhibit on adjacent faces measurement axes aligned at right angles to one another, and wherein the devices exhibit on mutually opposing faces measurement axes aligned opposite to one another.  
   
   
       10 . A method for the measurement of a speed and a rotation of a system, wherein the method comprises for each of six devices of the system, arranged in different spatial directions: 
 the generation of at least one emission,    the transfer of respectively at least one part of the at least one emission on at least two paths with a respective known wavelength and a respective known propagation speed, wherein a translatory movement of the device causes a phase displacement between the emission parts propagating on the at least two paths,    the detection of the emission parts leaving the at least two paths and    the determination of the speed of the device in at least one spatial direction by the evaluation of a change in the phase displacement between the detected emission parts in comparison with a phase displacement with the device at rest, wherein a change in the phase displacement of the emission parts due to a rotational movement of the device is prevented or compensated for,    wherein the method further comprises a determination of the speed and the rotation of the system from the speeds detected for the respective device.    
   
   
       11 . The method according to  claim 10 , wherein the at least six devices are arranged on the six faces of a cube, wherein the devices on adjacent faces determine the speed in spatial directions at right angles to one another, and wherein the devices on opposite faces determine the speed in spatial directions opposed to one another.  
   
   
       12 . The system according to  claim 1 , wherein the at least two paths of a respective device exhibit different geometric lengths.  
   
   
       13 . The system according to  claim 1 , wherein, in order to prevent a change in the phase displacement between the emission parts detected by the evaluation means due to a rotational movement of a respective device, each of the at least two paths of the device exhibits, outside an imaginary straight line, path parts of essentially equal size on opposite sides of this straight line.  
   
   
       14 . The system according to  claim 1 , further comprising detection means designed for the detection of a rotational movement of a respective device, wherein the evaluation means are designed for the compensation of a change incurred by a rotational movement on the at least two paths of the respective device in the phase displacement between detected emission parts on the basis of information from the detection means.  
   
   
       15 . The system according to  claim 1 , wherein the at least two paths of the respective device are designed in such a way that they exhibit at least one common path section, which is run through in opposite directions by the emission parts fed into the at least two paths.  
   
   
       16 . The system according to  claim 15 , wherein the common path section is designed in such a way that it exhibits a path part which is run through by one of the emission parts essentially in the direction of measurement of the respective device and a path part which is run through by this emission part essentially in the opposite direction, wherein the two path parts, with the device at rest, exhibit a different physical length.  
   
   
       17 . The system according to  claim 1 , further comprising an acceleration sensor designed for creating a reference to the local gravity normal.  
   
   
       18 . The system according to  claim 1 , wherein the at least six devices are arranged on the six faces of a cube, wherein the devices exhibit on adjacent faces measurement axes aligned at right angles to one another, and wherein the devices exhibit on mutually opposing faces measurement axes aligned opposite to one another.